# Copyright 2025 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

name: "Automated PR Review"
# yamllint disable-line rule:truthy
on:
  pull_request:
    types:
      - opened
      - synchronize
      - labeled

jobs:
  pr-review:
    # Run only if the PR has the 'automated-review' label
    if: contains(github.event.pull_request.labels.*.name, 'automated-review')
    permissions:
      contents: read
      id-token: write
      pull-requests: write
    runs-on: ubuntu-latest
    steps:
      - id: checkout
        name: Checkout repository
        uses: actions/checkout@v4
        with:
          fetch-depth: 0  # Need full history for diffing

      - id: gcp-auth
        name: Authenticate to Google Cloud
        uses: google-github-actions/auth@v2
        with:
          # yamllint disable-line rule:line-length
          workload_identity_provider: ${{ vars.REVIEWS_WIF_PROVIDER }}
          service_account: ${{ vars.REVIEWS_WIF_SA }}
          access_token_lifetime: 900s

      - id: setup-python
        name: Set up Python
        uses: actions/setup-python@v5
        with:
          python-version: '3.11'

      - id: install-deps
        name: Install Dependencies
        run: |
          pip install google-cloud-aiplatform

      - id: generate-diff
        name: Generate PR Diff
        env:
          BASE_REF: ${{ github.event.pull_request.base.ref }}
          BASE_SHA: ${{ github.event.pull_request.base.sha }}
          HEAD_SHA: ${{ github.event.pull_request.head.sha }}
        run: |
          # Fetch the target branch to ensure we have the base commit to compare against
          git fetch origin "$BASE_REF":"$BASE_REF"

          # Generate the diff between the PR base and the PR head
          git diff "$BASE_SHA"..."$HEAD_SHA" > pr.diff

      - id: run-review
        name: Run Gemini PR Review
        env:
          VERTEX_PROJECT: ${{ vars.REVIEWS_VERTEX_PROJECT }}
        run: |
          # The script prints the review to stdout, which we capture into a file

          python3 tools/pr_review.py \
            --project "$VERTEX_PROJECT" \
            --diff-file pr.diff > review_output.md
      - id: pr-comment
        name: Post comment to Pull Request
        uses: actions/github-script@v7
        with:
          script: |
            const fs = require('fs');
            const reviewContent = fs.readFileSync('review_output.md', 'utf8');
            const output = `### Automated PR Review 🤖\n\n${reviewContent}`;

            github.rest.issues.createComment({
              issue_number: context.issue.number,
              owner: context.repo.owner,
              repo: context.repo.repo,
              body: output
            })